It is the aim of this proposal to investigate the possible biochemical mechanisms which underlie the adrenergic regulation of the tissues of the blood-brain barrier (microvasculature) and blood-CSF barrier (choroid plexus). The research will utilize biochemical and pharmacological techniques applied to isolated tissue preparations, cell suspensions, and cell culture preparations, some of which were developed in our laboratory over the past three years. These techniques will allow us to determine, in vitro, the effects of adrenergic agents on various transport (e.g., Na+, K+ fluxes) and enzymatic processes (e.g., carbonic anhydrase; ATPase; protein kinase) in cerebral vascular endothelium and choroid plexus epithelium. They will also be used to investigate certain other possible regulators of barrier function, such as vasopressin. We hope to acquire information that will improve our understanding of cerebral edema and hydrocephalus as well as the mechanisms by which drugs and nutrients gain access to the brain.